1. Field of the Invention
The present invention relates to a semiconductor device having a package which has substantially the same size as that of a semiconductor chip and is particularly suitable for a multiple-output semiconductor chip, as well as a method for manufacturing the same and a method for mounting the same.
2. Description of the Related Art
Conventionally, packages having substantially the same size as semiconductor chips of this type are called a chip-size package, a xcexc-BGA, a chip-scale package (CSP), and the like, and various types of such packages have been developed. FIG. 24 is a fragmentary perspective view of a semiconductor device having a package of a conventional molded type. This semiconductor device is manufactured by forming bumps 242 on electrode pads of an LSI chip 241, then by resin-encapsulating the LSI chip 241 with a mold resin 243 having substantially the same size as that of the LSI by using a transfer mold, and finally by depositing solder balls 244 on external electrodes.
FIG. 25 shows a cross-sectional view of a semiconductor device having a conventional film (film carrier tape) type. This semiconductor device is manufactured as follows. The surface of an LSI chip 251 is coated with an elastic adhesive (elastomer) 252, a polyimide film 255 on which inner leads 253 and external connection pads 254 have been formed is secured to the surface of the LSI chip 251 by means of the elastic adhesive 252, the inner leads 253 are bonded to the chip electrode pads of the LSI chip 251, and solder balls 256 are deposited on the external connection pads 254.
In addition, FIG. 26 is a cross-sectional view of a semiconductor device having a package of a conventional flip chip bonding type. This semiconductor device is manufactured by forming bumps 262 on the surface of an LSI chip 261, then by effecting face-down bonding the LSI chip 261 on a substrate 263 formed of a ceramic or an organic material, and then by encapsulating the chip by using an encapsulating resin 264. Solder balls 265 are deposited on the reverse surface of the substrate 263. If the package of any one of the types shown in FIGS. 24 to 26 is used, it is possible to manufacture a semiconductor device having a package of substantially the same size as that of the LSI.
However, with the semiconductor device shown in FIG. 24, an exclusive-use transfer mold is required, which has been a factor hampering the effort in lowering the cost of the semiconductor devices.
In addition, with the semiconductor device shown in FIG. 25, since a special elastic adhesive is used between the LSI chip and the tape, the contamination of or the damage to the surface of the LSI chip can occur, possibly deteriorating the reliability. In addition, when the LSI chip and the inner leads are connected, a single bonding method in which the leads are bonded one at a time is used. As a result, in multiple-output packages, the bonding time becomes prolonged, and has constituted a factor hampering the effort in lowering the cost of the semiconductor devices.
Furthermore, with the semiconductor device shown in FIG. 26, the substrate is multilayered in the multiple-output package and is expensive, and in the case of an LSI chip having a large size, the difference in the coefficient of thermal expansion between the substrate and the LSI chip in some cases constitutes a problem in the reliability.
In view of the above-described circumstances, it is an object of the present invention to provide a low-cost, highly reliable semiconductor device suitable for use in a case where a multiple-output LSI chip, as well as a method for manufacturing the same and a method for mounting the same, thereby overcoming the above-described drawbacks of the conventional art.
To this end, in accordance with a first aspect of the present invention, there is provided a semiconductor device comprising a package film including: a device-mounting film portion on which a semiconductor chip is mounted; an external-connection film portion arranged on the device-mounting film portion and having an external electrode pad formed thereon; a bending portion provided between an end portion of the device-mounting film portion and an end portion of the external-connection film portion; and an inner lead for electrically connecting an electrode pad of the semiconductor chip and the external electrode pad via the bending portion.
In accordance with a second aspect of the present invention, there is provided a semiconductor device comprising a package film including: a device-mounting film portion on which a semiconductor chip is mounted such that the device-mounting film portion faces an obverse surface of the semiconductor chip; an external-connection film portion arranged on a reverse surface of the semiconductor chip and having an external electrode pad formed thereon; a bending portion provided between an end portion of the device-mounting film portion and an end portion of the external-connection film portion; and an inner lead for electrically connecting an electrode pad of the semiconductor chip and the external electrode pad via the bending portion.
In accordance with a third aspect of the present invention, there is provided a semiconductor device comprising a package film on which a semiconductor chip having an electrode pad arranged in a region along a central portion of the chip or a center line of the chip is mounted, wherein the package film includes: a device hole formed in a region along a central portion thereof or a center line thereof in correspondence with the region where the electrode pad of the semiconductor chip is formed; an external electrode pad formed in a region other than the region where the device hole is formed; and an inner lead connecting the electrode pad of the semiconductor chip and the external electrode pad.
In accordance with a fourth aspect of the present invention, there is provided a semiconductor device comprising a package film on which a semiconductor chip having an electrode pad arranged in a peripheral portion of the chip is mounted, wherein the package film includes: a device hole formed in a peripheral portion thereof in correspondence with the region where the electrode pad of the semiconductor chip is formed; an external electrode pad formed in a region other than the region where the device hole is formed; and an inner lead connecting the electrode pad of the semiconductor chip and the external electrode pad, wherein a space between the package film and a surface of the semiconductor chip is fixed by an encapsulating resin.
In accordance with a fifth aspect of the present invention, there is provided a semiconductor device comprising a package film including: a device-mounting film portion on which a semiconductor chip having an electrode pad arranged in a predetermined region is mounted such that the device-mounting film portion faces an obverse surface of the semiconductor chip; an external-connection film portion arranged on a reverse surface of the semiconductor chip and having an external electrode pad formed thereon; a bending portion provided between an end portion of the device-mounting film portion and an end portion of the external-connection film portion; and an inner lead, wherein the device-mounting film portion has a device hole formed in a predetermined region in correspondence with a region where an electrode pad of the semiconductor chip is formed and an external electrode pad formed in a region other than the region where the device hole is formed, and the inner lead electrically connects the electrode pad of the semiconductor chip and the external electrode pad of the device-mounting film portion, and electrically connects the electrode pad of the semiconductor chip and the external-connection film portion via the bending portion.
In accordance with a sixth aspect of the present invention, there is provided a method for manufacturing a semiconductor device, comprising the steps of: preparing a package film having a planar configuration whose region is divided into a device-mounting film portion having a device hole forming therein, an external-connection film portion, and a bent portion located between the device-mounting film portion and the external-connection film portion, an external electrode pad being formed on the external-connection film portion on a first surface side of the package film, an inner lead being formed in such a manner as to lead from the device hole to the external electrode pad via the bending portion; mounting a semiconductor chip on the device-mounting film portion on the first surface side by bonding the inner lead to an electrode pad of the semiconductor chip in a region where the device hole is formed; and bending the external-connection film portion at the bending portion 180xc2x0 toward a second surface side of the package film and fixing the same.
In accordance with a seventh aspect of the present invention, there is provided a method for manufacturing a semiconductor device, comprising the steps of: preparing a package film having a planar configuration whose region is divided into a device-mounting film portion having a device hole forming therein, an external-connection film portion, and a bent portion located between the device-mounting film portion and the external-connection film portion, an external electrode pad being formed on the external-connection film portion on a first surface side of the package film, an inner lead being formed in such a manner as to lead from the device hole to the external electrode pad via the bending portion; mounting a semiconductor chip on the device-mounting film portion on a second surface side of the package film by bonding the inner lead to an electrode pad on an obverse surface of the semiconductor chip in a region where the device hole is formed; and bending the external-connection film portion at the bending portion 180xc2x0 toward a reverse surface side of the semiconductor chip and fixing the same to the reverse surface.
In accordance with an eighth aspect of the present invention, there is provided a method for manufacturing a semiconductor device, comprising the steps of: preparing a semiconductor chip having an electrode pad arranged in a region along a central portion of the chip or a center line of the chip, as well as a package film having a device hole formed in a region along a central portion thereof or a center line thereof in correspondence with the region where the electrode pad of the semiconductor chip is formed, an external electrode pad being formed on an external connection surface side of the package film in a region other than the region where the device hole is formed, an inner lead being formed in such a manner as to lead from the device hole to the external electrode; and mounting the semiconductor chip on a device mounting surface side of the package film by bonding the inner lead to the electrode pad of the semiconductor chip in the region where the device hole is formed.
In accordance with a ninth aspect of the present invention, there is provided a method for manufacturing a semiconductor device, comprising the steps of: preparing a semiconductor chip having an electrode pad arranged in a peripheral portion of the chip, as well as a package film having a device hole formed in a peripheral portion thereof in correspondence with the region where the electrode pad of the semiconductor chip is formed, an external electrode pad being formed on an external connection surface side of the package film in a region other than the region where the device hole is formed, an inner lead being formed in such a manner as to lead from the device hole to the external electrode; and mounting the semiconductor chip on a device mounting surface side of the package film by bonding the inner lead to the electrode pad of the semiconductor chip in the region where the device hole is formed, and by allowing an encapsulating resin to flow into a space between the package film and an obverse surface of the semiconductor chip.
In accordance with a 10th aspect of the present invention, there is provided a method for manufacturing a semiconductor device, comprising the steps of: preparing a semiconductor chip having electrode pads arranged in a predetermined region thereof, as well as a package film having a planar configuration whose region is divided into a device-mounting film portion having a device hole forming in a determined region thereof, an external-connection film portion, and a bent portion located between the device-mounting film portion and the external-connection film portion, external electrode pads being formed on the external-connection film portion on a first surface side of the package film and in a region other than the region where the device hole is formed in the device-mounting film portion on the first surface side, inner leads being formed in such a manner as to lead from the device hole to respective the external electrode pads; mounting the semiconductor chip on the device-mounting film portion on a second surface side of the package film by bonding the inner leads to the electrode pads on an obverse surface of the semiconductor chip in a region where the device hole is formed; and bending the external-connection film portion at the bending portion 180xc2x0 toward a reverse surface side of the semiconductor chip and fixing the same to the reverse surface.
In accordance with an 11th aspect of the present invention, there is provided a method for mounting a semiconductor device on a mother board in close contact therewith, comprising the steps of: depositing solder balls on electrode pads of the mother board; and placing the semiconductor device on the mother board and melting the solder balls so as to electrically connect the electrode pads of the mother board and the external electrode pads of the semiconductor device
In accordance with a 12th aspect of the present invention, there is provided a method for mounting a semiconductor device in which a plurality of superposed semiconductor devices are mounted on a mother board, comprising the step of: causing the external electrode pads formed on one of the external-connection film portion and the device-mounting film portion of a first semiconductor device to be superposed on the electrode pads of the mother board, and causing the external electrode pads formed on one of the external-connection film portion and the device-mounting film portion of a second semiconductor device to be superposed on the external electrode pads formed on another film portion of the first semiconductor device, so as to electrically connect the superposed electrodes.
The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the invention when read in conjunction with the accompanying drawings.